In recent years, the definition of a display device has been increased. As the definition of a display device becomes higher, the numbers of circuits and wirings for sending image signals or supplying power to the display device tend to increase. Since the numbers of circuits and wirings are increased, the power consumption of the display device is also likely to increase.
A technology for reducing the number of operations of writing signals (hereinafter also referred to as refresh operations in some cases) during successive display of the same image (still image) is known as a method for reducing the power consumption of a display device (Patent Document 1). The frequency of refresh operations is referred to as a refresh rate.